sql21（Leetcode1174即时食物配送2）

代码：

# Write your MySQL query statement belowselect round (sum(order_date = customer_pref_delivery_date) * 100 /count(*),2
) as immediate_percentage
from Delivery
where (customer_id, order_date) in (select customer_id, min(order_date)from deliverygroup by customer_id
)